Amphimachairodus coloradensis (Amphimachairodus coloradensis Cook, 1922)
Time period: endemic to North America during the late Miocene from 7,0 to 4,5 Ma.
Size: 1,8 m in length, 95 cm in height, 160 kg of weight.
Amphimachairodus coloradensis was apparently significantly larger, about 1 m at the shoulder, according to skeletal and life reconstructions. If accurate, this would make A. coloradensis one of the largest felids.The skull of Machairodus was noticeably narrow compared with the skulls of modern pantherine big cats, and the orbits were relatively small. The canines were long, thin and flattened from side to side but broad from front to back like the blade of a knife, as in Homotherium. The front and back edges of the canines were serrated when they first grew, but these serrations were worn down in the first few years of the animal's life.